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# dialects/oracle/oracledb.py
# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: https://www.opensource.org/licenses/mit-license.php
# mypy: ignore-errors
r"""
.. dialect:: oracle+oracledb
:name: python-oracledb
:dbapi: oracledb
:connectstring: oracle+oracledb://user:pass@hostname:port[/dbname][?service_name=<service>[&key=value&key=value...]]
:url: https://oracle.github.io/python-oracledb/
python-oracledb is released by Oracle to supersede the cx_Oracle driver.
It is fully compatible with cx_Oracle and features both a "thin" client
mode that requires no dependencies, as well as a "thick" mode that uses
the Oracle Client Interface in the same way as cx_Oracle.
.. seealso::
:ref:`cx_oracle` - all of cx_Oracle's notes apply to the oracledb driver
as well.
The SQLAlchemy ``oracledb`` dialect provides both a sync and an async
implementation under the same dialect name. The proper version is
selected depending on how the engine is created:
* calling :func:`_sa.create_engine` with ``oracle+oracledb://...`` will
automatically select the sync version, e.g.::
from sqlalchemy import create_engine
sync_engine = create_engine("oracle+oracledb://scott:tiger@localhost/?service_name=XEPDB1")
* calling :func:`_asyncio.create_async_engine` with
``oracle+oracledb://...`` will automatically select the async version,
e.g.::
from sqlalchemy.ext.asyncio import create_async_engine
asyncio_engine = create_async_engine("oracle+oracledb://scott:tiger@localhost/?service_name=XEPDB1")
The asyncio version of the dialect may also be specified explicitly using the
``oracledb_async`` suffix, as::
from sqlalchemy.ext.asyncio import create_async_engine
asyncio_engine = create_async_engine("oracle+oracledb_async://scott:tiger@localhost/?service_name=XEPDB1")
.. versionadded:: 2.0.25 added support for the async version of oracledb.
Thick mode support
------------------
By default the ``python-oracledb`` is started in thin mode, that does not
require oracle client libraries to be installed in the system. The
``python-oracledb`` driver also support a "thick" mode, that behaves
similarly to ``cx_oracle`` and requires that Oracle Client Interface (OCI)
is installed.
To enable this mode, the user may call ``oracledb.init_oracle_client``
manually, or by passing the parameter ``thick_mode=True`` to
:func:`_sa.create_engine`. To pass custom arguments to ``init_oracle_client``,
like the ``lib_dir`` path, a dict may be passed to this parameter, as in::
engine = sa.create_engine("oracle+oracledb://...", thick_mode={
"lib_dir": "/path/to/oracle/client/lib", "driver_name": "my-app"
})
.. seealso::
https://python-oracledb.readthedocs.io/en/latest/api_manual/module.html#oracledb.init_oracle_client
.. versionadded:: 2.0.0 added support for oracledb driver.
""" # noqa
from __future__ import annotations
import collections
import re
from typing import Any
from typing import TYPE_CHECKING
from .cx_oracle import OracleDialect_cx_oracle as _OracleDialect_cx_oracle
from ... import exc
from ... import pool
from ...connectors.asyncio import AsyncAdapt_dbapi_connection
from ...connectors.asyncio import AsyncAdapt_dbapi_cursor
from ...connectors.asyncio import AsyncAdaptFallback_dbapi_connection
from ...util import asbool
from ...util import await_fallback
from ...util import await_only
if TYPE_CHECKING:
from oracledb import AsyncConnection
from oracledb import AsyncCursor
class OracleDialect_oracledb(_OracleDialect_cx_oracle):
supports_statement_cache = True
driver = "oracledb"
_min_version = (1,)
def __init__(
self,
auto_convert_lobs=True,
coerce_to_decimal=True,
arraysize=None,
encoding_errors=None,
thick_mode=None,
**kwargs,
):
super().__init__(
auto_convert_lobs,
coerce_to_decimal,
arraysize,
encoding_errors,
**kwargs,
)
if self.dbapi is not None and (
thick_mode or isinstance(thick_mode, dict)
):
kw = thick_mode if isinstance(thick_mode, dict) else {}
self.dbapi.init_oracle_client(**kw)
@classmethod
def import_dbapi(cls):
import oracledb
return oracledb
@classmethod
def is_thin_mode(cls, connection):
return connection.connection.dbapi_connection.thin
@classmethod
def get_async_dialect_cls(cls, url):
return OracleDialectAsync_oracledb
def _load_version(self, dbapi_module):
version = (0, 0, 0)
if dbapi_module is not None:
m = re.match(r"(\d+)\.(\d+)(?:\.(\d+))?", dbapi_module.version)
if m:
version = tuple(
int(x) for x in m.group(1, 2, 3) if x is not None
)
self.oracledb_ver = version
if (
self.oracledb_ver > (0, 0, 0)
and self.oracledb_ver < self._min_version
):
raise exc.InvalidRequestError(
f"oracledb version {self._min_version} and above are supported"
)
class AsyncAdapt_oracledb_cursor(AsyncAdapt_dbapi_cursor):
_cursor: AsyncCursor
__slots__ = ()
@property
def outputtypehandler(self):
return self._cursor.outputtypehandler
@outputtypehandler.setter
def outputtypehandler(self, value):
self._cursor.outputtypehandler = value
def var(self, *args, **kwargs):
return self._cursor.var(*args, **kwargs)
def close(self):
self._rows.clear()
self._cursor.close()
def setinputsizes(self, *args: Any, **kwargs: Any) -> Any:
return self._cursor.setinputsizes(*args, **kwargs)
def _aenter_cursor(self, cursor: AsyncCursor) -> AsyncCursor:
try:
return cursor.__enter__()
except Exception as error:
self._adapt_connection._handle_exception(error)
async def _execute_async(self, operation, parameters):
# override to not use mutex, oracledb already has mutex
if parameters is None:
result = await self._cursor.execute(operation)
else:
result = await self._cursor.execute(operation, parameters)
if self._cursor.description and not self.server_side:
self._rows = collections.deque(await self._cursor.fetchall())
return result
async def _executemany_async(
self,
operation,
seq_of_parameters,
):
# override to not use mutex, oracledb already has mutex
return await self._cursor.executemany(operation, seq_of_parameters)
def __enter__(self):
return self
def __exit__(self, type_: Any, value: Any, traceback: Any) -> None:
self.close()
class AsyncAdapt_oracledb_connection(AsyncAdapt_dbapi_connection):
_connection: AsyncConnection
__slots__ = ()
thin = True
_cursor_cls = AsyncAdapt_oracledb_cursor
_ss_cursor_cls = None
@property
def autocommit(self):
return self._connection.autocommit
@autocommit.setter
def autocommit(self, value):
self._connection.autocommit = value
@property
def outputtypehandler(self):
return self._connection.outputtypehandler
@outputtypehandler.setter
def outputtypehandler(self, value):
self._connection.outputtypehandler = value
@property
def version(self):
return self._connection.version
@property
def stmtcachesize(self):
return self._connection.stmtcachesize
@stmtcachesize.setter
def stmtcachesize(self, value):
self._connection.stmtcachesize = value
def cursor(self):
return AsyncAdapt_oracledb_cursor(self)
class AsyncAdaptFallback_oracledb_connection(
AsyncAdaptFallback_dbapi_connection, AsyncAdapt_oracledb_connection
):
__slots__ = ()
class OracledbAdaptDBAPI:
def __init__(self, oracledb) -> None:
self.oracledb = oracledb
for k, v in self.oracledb.__dict__.items():
if k != "connect":
self.__dict__[k] = v
def connect(self, *arg, **kw):
async_fallback = kw.pop("async_fallback", False)
creator_fn = kw.pop("async_creator_fn", self.oracledb.connect_async)
if asbool(async_fallback):
return AsyncAdaptFallback_oracledb_connection(
self, await_fallback(creator_fn(*arg, **kw))
)
else:
return AsyncAdapt_oracledb_connection(
self, await_only(creator_fn(*arg, **kw))
)
class OracleDialectAsync_oracledb(OracleDialect_oracledb):
is_async = True
supports_statement_cache = True
_min_version = (2,)
# thick_mode mode is not supported by asyncio, oracledb will raise
@classmethod
def import_dbapi(cls):
import oracledb
return OracledbAdaptDBAPI(oracledb)
@classmethod
def get_pool_class(cls, url):
async_fallback = url.query.get("async_fallback", False)
if asbool(async_fallback):
return pool.FallbackAsyncAdaptedQueuePool
else:
return pool.AsyncAdaptedQueuePool
def get_driver_connection(self, connection):
return connection._connection
dialect = OracleDialect_oracledb
dialect_async = OracleDialectAsync_oracledb